#include <cs50.h>
#include <stdio.h>
#include <math.h>

int main(void)
{
    int start = 0;
    int end = 0;
    // TODO: Prompt for start size
    do{
        start = get_int("Start size: ");
    }
    while(start < 9);

    // TODO: Prompt for end size
    do{
        end = get_int("End size: ");
    }
    while(end < start);
    // TODO: Calculate number of years until we reach threshold
    double years;
    years = floor(log10((double)end / (double)start) / log10(13.0 / 12.0));





    // TODO: Print number of years
    printf("Years: %.0f",years);
}
